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121.
To optimize dietary protein level in relation to growth, semipurified diets with an essential amino acid profile similar to that of the soft body profile were fed for 59 days to young greenlip abalone, Haliotis laevigata (initial shell length, 15–25 mm). Animals were housed in 10-L acrylic tanks, with flow-through seawater supplied at 1 L min–1 (20 °C, salinity= 36 g L–1). Protein level of feeds ranged from 122 g kg–1 to 461 g kg–1 crude protein (CP) on an 'as is' basis. Second-order polynomial regression analysis of specific growth rate indicated that maximal growth occurs at 270 g kg–1 CP. The protein and energy components of the feed were estimated to have a digestibility of 71.7% and 55.6%, respectively.  相似文献   
122.
通过测定不同氨氮条件下的九孔鲍内脏囊中的过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活力,观察氨氮对九孔鲍CAT和SOD酶活力的影响,实验结果表明:不同氨氮浓度下的这两种酶活力不同,CAT活力随氨氮浓度的升降而变化,当氨氮浓度为3-4mg/L时,其活力高于对照组,当浓工增大至5-6mg/L时,CAT活力低于对照组;在氨氮为1-4mg/L时,SOD活力随氨氮浓度增大而上升,在4mg/L时达到最运,而当氨氮增至5-6mg/L时,SOD活力下降,不同温度下的氨氮浓度对九孔鲍的CAT和SOD酶活力变化有一定的影响。  相似文献   
123.
对皱纹盘鲍外套膜的组织学观察发现,外套膜主要由上、下表皮和其间的结缔组织组成。上、下表皮细胞可分为高柱状细胞、弱嗜碱性腺细胞和颗粒状腺细胞3种,结缔组织中富含纤维、血管和神经。聚合体细胞发育形成结缔组织中的粘液泡腺细胞。  相似文献   
124.
为通过杂交育种解决南日鲍种质退化问题以促进鲍养殖效益,分别选取2012年10月份开展的南日鲍(♀)与皱纹盘鲍大连群体(♂)、盘鲍日本群体(♂)杂交所得的苗种以及南日鲍自交所得的3种苗种,于2013年3月份在海区水质情况良好的同一渔排吊笼养殖进行对比试验,试验分为3组,每组2 500个鲍苗,试验390d左右,观察它们的生长情况,测定鲍的体长、体重,分别统计每组鲍的数量。结果表明:分苗前,杂交鲍苗的生长速度、度夏养殖成活率均显著高于自交所得鲍苗(P0.05);而南日鲍(♀)×盘鲍(♂)杂交所得鲍苗的生长速度和养殖成活率略高于南日鲍(♀)×皱纹盘鲍(♂),但差异不显著(P0.05);当年秋季分苗后,养殖鲍的生长速度和养殖成活率依次为:南日鲍(♀)×盘鲍(♂)南日鲍(♀)×皱纹盘鲍(♂)南日鲍(♀)×南日鲍(♂),且3组之间差异显著(P0.05)。说明在鲍养殖生产中,采用杂交育种改良和优化鲍种质是切实可行的,可显著提高鲍的生长速度和养殖成活率。  相似文献   
125.
The increasing popularity of abalone as a seafood delicacy has led to the rapid development of abalone aquaculture worldwide. The commercial and economic importance of this industry has resulted in an increasing interest in the biology of this particular shellfish genus. In this study we focus on the identification of structural, functional and proliferative proteins in two species of abalone shellfish, Haliotis discus hannai and Haliotis tuberculata. Monoclonal and polyclonal antibodies that react with proteins in vertebrate and invertebrate tissues were selected and applied to abalone tissues. Cross sections of whole animals were analysed using avidin-biotin immunoperoxidase staining protocols. In total, twenty-four antibodies were tested on shellfish tissues. Six antibodies out of twenty-four detected antigens in Haliotis spp. Cytokeratins, proliferating cell nuclear antigen (PCNA), neuron specific enolase (NSE), laminin and vimentin were detected in abalone tissues. Positive immunohistochemical results were confirmed using western blot. The expression of these proteins aids in the characterisation of cell types present in abalone tissues, which contributes to a better understanding of the fundamental biology of this shellfish genus.  相似文献   
126.
TZE-KUEI  CHIOU  MENG-MEI  LAI 《Fisheries Science》2002,68(2):388-394
ABSTRACT: Differences in taste preference and the levels of extractive components and glycogen were compared between cooked meats of small abalone Haliotis diversicolor fed either gracilar (G-small abalone) or an artificial diet (A-small abalone). Using sensory tests, taste preference of cooked meats was significantly higher for A-small abalone than for G-small abalone. Results of clustering analysis and principal component analysis of chemical data also revealed that the two cooked meats differed from each other in terms of their measured constituent compositions irrespective of sampling periods. Compared with G-small abalone, A-small abalone meats were lower in taurine and arginine, but higher in glycine (Gly), glutamic acid (Glu), alanine, serine, proline, adenosine monophosphate (AMP), and glycogen. It is concluded that the discrepancy in the levels of taste-active components of abalone, such as Gly, Glu, and AMP, is likely to be responsible for the differences in taste preference between G- and A-small abalone cooked meats.  相似文献   
127.
光照强度对九孔鲍幼虫及幼鲍生长存活的影响   总被引:7,自引:0,他引:7       下载免费PDF全文
严正凛 《水产学报》2001,25(4):336-341
在自然光周期下,分别在高温长光照和低温短光照的两个节季节,采用控制光照强度的方法进行对九孔鲍幼虫及幼鲍50d左右培育的小型试验。结果表明,光照强度对附着基上摄食微藻的幼虫及幼鲍生长和存活等有重要的影响。对幼虫及幼鲍最适宜的光照强度,在高温长光照下为700-1200lx,在低温短光照下为1300-2000lx。选用适宜的光照强度在高温长光照和低温短光照下先后进行了3次经量育苗试验,获得了与小型试验相同的结果。  相似文献   
128.
以透射电镜与组织学方法研究 4 5日龄皱纹盘鲍 (Haliotisdiscushannai,壳长 2 .3 0~ 2 .4 0mm ,壳宽1.80~ 2 .10mm)的消化道。结果表明 :①食道分为前、中、后 3段 ;中段分为食物通道和食道侧囊 ,食道侧囊的分泌细胞含大量的囊泡和分泌颗粒 ,呈强的蛋白酶和非特异性酯酶活性 ;食道前段、食物通道及食道后段粘膜上皮由纤毛细胞和粘液细胞组成。②嗉囔粘膜上皮只有 1种细胞 ,细胞游离缘具有长达 4 .0 μm的密集微绒毛。③胃粘膜上皮由纤毛细胞和微绒毛细胞组成。④肠和直肠粘膜上皮由 5种细胞组成 ,即纤毛细胞、微绒毛细胞、分泌细胞、颗粒状腺细胞和粘液细胞 ,分泌细胞基部有少量的分泌颗粒。⑤存在于消化道各部位的微绒毛细胞游离缘均具密集的微绒毛 ,游离端质膜呈碱性磷酸酶活性 ;食道和肠的粘液细胞分泌粘多糖 ;食道、胃和肠的纤毛细胞游离缘具纤毛。  相似文献   
129.
The effect of animal size on the qualitative protein requirements of two size classes of Haliotis midae L. was assessed by feeding 12 semi‐purified single protein test diets (20% protein, 6% lipid) to juvenile and young adult animals (10–20‐ and 40–50‐mm initial shell length). The protein sources selected for the trial comprised four fishmeals, casein, spirulina, abalone viscera silage, brewery waste, torula yeast, carcass, sunflower and cotton seed meals. The results indicated that in terms of growth and feed efficiency, the fishmeals and spirulina were the most suitable candidates for use as primary protein sources in formulated feeds, and with the exceptions of the carcass meal and brewery waste, the remaining protein sources demonstrated promise as partial primary protein source replacements. Mean growth rates for the large and small abalone over the experimental period were 1.45 and 1.24 mm month?1 respectively. With respect to the larger size class of abalone, the smaller abalone displayed significantly reduced growth (F = 64.7, P < 0.0001), feed conversion ratio (F = 16.6, P < 0.0001) and protein efficiency (F = 26.8, P < 0.0001). Two‐way analysis of variance revealed significant interactions between protein source, animal size and feed conversion ratio (F = 2.4, P < 0.01) and growth (F = 5.4, P < 0.05), thus indicating that qualitative differences exist between the dietary protein requirements of the juvenile and young adult abalone.  相似文献   
130.
Oogenesis of abalone Haliotis discus hannai was examined histologically during a single spawning season using broodstock of various maturation conditions, which were controlled by effective accumulative temperature (EAT). The quality of eggs spawned was determined in relation to oogenesis. For histological examinations, three to five females were sacrificed at 300, 600, 850, 1050, and 1150 °C days EAT, without induction of artificial spawning. Other females were successfully induced to spawn at 700 °C days EAT and were reared following spawning. Three of these females were then sacrificed every 200 °C days EAT until 1300 °C days EAT. Gonad histology showed that two oocyte cohorts matured in H. discus hannai ovaries during a single spawning season. One mature oocyte cohort could be spawned in multiple times. The second oocyte cohort started developing after the first oocyte cohort had been spawned or reabsorbed, and became fully mature 400 °C days EAT after the first cohort was depleted. For egg quality measurements, three to five females were successfully induced to spawn at 850, 1050, 1150, 1900, and 2350 °C days EAT (Experiment 1). Three females were induced to spawn twice, at 700 and 1500 °C days EAT, resulting in two batches of eggs from the same individuals (Experiment 2). Total lipid and protein content of eggs were measured and were greater in eggs from the second cohort than in eggs from the first cohort. No carbohydrates were detected in eggs and there was no difference in cytoplasm volume between the two cohorts. In hatcheries producing H. discus hannai, it is important to increase post-larval starvation tolerance by increasing the quality of eggs, to yield higher and more consistent survival. The results of this study suggest that H. discus hannai hatcheries should use eggs from the second oocyte cohort, which are of higher quality, rather than eggs from the first oocyte cohort.  相似文献   
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